Improvement in riffle-boxes



RHESAI. DUNNING, OF NORTH SAN JUAN, CALIFORNIA.

IMPROVEMENT IN RIFFLE-BoxEs.

Specification forming part of Letters Patent No. 58,079, dated September 1S, 1866.

To all whom it may concern Be it known that I, RHEsA HALL DUNNING, of North San Juan, county of Nevada, State of California, have inven ted a certain new and useful Itile-Box for Saving Gold; and I do hereby declare the following description and `acconclpanying drawings are sufficient to enable any person skilled in the art to make and 4 use my said invention without further invention or experiment.

' The nature of my invention consists in the employment of a separate box t0 be placed in a sluice used for hydraulic mining, which receives the gold as it divides the Wateror falls through the bars of the flume.

Referring `to the drawings, Figure l represents a section ot' a flume, sluiceway, and box, taken in line Ot' 5 and 6, as shown in Fig. 4; Fig. 2, also section of tinme, box, and sluice, taken in line 3 and 4, Fig. 4; Fig. 3, a section of box, taken in line 3 and 4, Fig. 4;. Fig. 4, a top View or plan of box; Fig. 5, cross-section of box.

A A, &c., represent the flume through which the gravel or dirt and water is admitted over little-bars in'the usual way, and is placed at right angles with the sluiceway, the tail end extending to within about six inches, more or less, of the outer edge of the sluiceway B, suiiicient to allow the gravel to clearitseit' from the ritlle-box C by the force of the water, while the coarser pieces of gold, which have not passed through the riflle-bars, but have been carried to the edge of the tail of the flume, being of Va specific graxv'ity nineteen times greater than that otl the water, break the current of the Water and fall into the box C.

The box C, I construct of Wood or other niaterial, so that it will easily slide along the bottom of the sluiceway and not bind at the sides, and place it directly under the tail of the iiume at the head of the sluice, reaching to Within about six inches, more or less, of the top of the sluieeway.

Across the riftle-box C, I place a dam-wall, I), of plank or other material, near the tail end of the box, leaving a space of about six inches between it and the tail end of the box, and of about one-half the height of the sides and head-board of said box.' A very good substitute for this darn-wall may be had by placing a board edgewise across the bottom of the sluice-box 5 or a bucket or vessel of any kind may be used, in which ease the Water and debris will be allowed to boil over all around instead of only over one part of the vessel. A

It will be found in the operation of my rifiiebox that the Water, liner gravel, and gold which pass through the riiiie-bars ot' the flume will fall directly into the box, and' the force and constant agitation of the water will carry oft' the dbris over the dain-wall D, and ont through the tailway of the sluice.

Should the force of the water be so greatas tobear over the dani-Wall any particles ot gold, they being so much heavier than the water and the force exerted by its fall, the gold in passing over the dani-wall will break the current and fall onto the tailway of the little-box, where it will remain near the daniwall, 0r be found in the riftle below the boxin the slnice, and not be carried down to the tail of the sluice and lost, as is often the case where no rifliebox is used.

Having thus described my invention, what l claim, and desire to secure by Letters Patent, is-

The riflie-box C, and dam-wall D, or their equivalents, to be employed for saving gold at any `point Where there is a divide of water, substantially as described.

In witness whereof I have hereunto set my hand and seal this 16th day of March, A. D. 1866. 

